I have that exact same model printer and the Brother drivers didn't work for me either. I just let the wizard set it up as a 2170w and it works fine for me. Don't uninstall the driver you have already added, just add a new printer and let Ubuntu pick the driver for you, print to it, and if it works you can just change the default printer to that one. That way if it works, great, if it dosen't, no loss.

I have a Brother HL-2270DW and I solved installing it as "Generic PCL Laser Printer", however a workaround (not so convenient in my opinion) for the Brother original driver is to print your document as .ps file and then print that file.

This issue is related to CUPS 1.6.x introduced with Ubuntu 12.10, because with Ubuntu 12.04 the printing margins are OK.